1. Field of the Invention
The present invention relates to a cosmetic or dermatological preparation which is obtainable by combining collagen and/or a derivative thereof, chitosan and/or a derivative thereof and glycosylaminoglycan and/or a derivative thereof with one or more substances which exhibit a beneficial effect when applied to healthy, injured or deseased skin. In one aspect, the preparation may comprise at least one nutrient medium phase for skin cells or corneal cells in combination with an aerogel or hydrogel matrix which comprises the above collagen/chitosan/glycosylaminoglycan combination. The invention further relates to cell culture media as aqueous phase in combination with the above matrix in synergistic use with polyurethanes which are employed for physiological wound healing or scar reduction.
2. Discussion of Background Information
Various circulations exist within the human body, such as the blood circulation, the lymphatic system and the intracellular and extracellular tissue fluids. The composition of the solvent “water” with its mineral and bioorganic constituents in these various “transport media” is approximately the same and is based, highly simplified, on salts, amino acids, vitamins, sugars, proteins and proteids, and trace elements. During evolution, our body has learnt to create within these fluids “communication networks” and nutritional strategies, and an equilibrium of catabolic to anabolic processes, which make the complex life of our multicellular body possible. In this environment, our body has learnt to construct from its “single individuals”, the cells, a complicated but efficient network of direct and mediator-related contacts. These “communication pathways” function efficiently and harmlessly only if the natural dynamic equilibrium of our body, the so-called “homeostasis”, is maintained. If cells are removed from the tissue assemblage or if the homeostasis in the tissue assemblage is impaired, it is no longer possible for individual cells to exist or for tissues to function healthily. The medical and biosciences have for decades looked for possibilities of cultivating tissues or individual cells in suitable environmental conditions outside the body. This was successful only when it was possible to simulate as perfectly as possible the living conditions in the body for the single cells or tissue constituents to be cultivated.
Thus, if cells are removed from intact tissue, they must be cultivated in environments which come as close as possible to the natural living conditions in the body. Requirements for this are supply and transport away of nutrients, and the presence of vital factors.
These environments are well-defined compositions of mineral and biomaterials which are known in science as cell culture media. Cell culture media are obtainable from suitable specialist retailers as powder or liquid media and have slightly different compositions depending on the nature of the cells or tissue constituents to be cultivated. Cell culture media are used in liquid form. With a suitable composition, they make it possible to maintain or even multiply microorganisms or cells in culture, i.e., outside the body.
In the course of tissue research it has been possible to identify and investigate the individual needs of cells and cells in intact tissues. In this connection, the ratio of mineral and bioorganic substances of a cell culture medium is slightly variable from cell type to cell type and must be ascertained accurately for optimized survival and growth. The composition of the cell culture medium always depends on the requirements of the cells to be grown. A distinction is made between synthetic media, whose ingredients are accurately known on the basis of pure substances, and complex media, whose exact composition may vary and is in part not accurately known. Cell culture media usually comprise, besides water, a carbon source and a nitrogen source, phosphate compounds and sulfur compounds, and minerals and, optionally, growth promoters and/or vitamins.
If the compositions of the media are suitable, the cells are able to multiply and produce the factors necessary for survival “in situ” by themselves.
In order to generate good growth of the cells, serum is frequently added to the cell culture media. The serum has a complicated composition and provides the cells with, inter alia, hormones, adhesion factors, and amino acids. Culture media which contain serum are, however, costly and do not allow thermal sterilization. One therefore usually tries to make do with media which contain no serum. Serum-free culture media make it possible to cultivate cells under controlled and defined conditions, so that unwanted effects due to variations in the serum composition are eliminated. In addition, contamination of the cell cultures with viruses and bacteria is reduced when using serum-free media.
It is known that skin cells can be kept alive particularly well-preserved and for long periods of time and can even be induced to grow and differentiate in one-, two- and three-dimensional cultures by optimizing the ingredients in the culture medium. It has also been possible to demonstrate that suitable media also make possible the production of growth factors in situ.
When there are extreme changes in the skin resulting from extensive burns or chills, the integrity and the functionality of the cutaneous tissue may be so impaired that the skin is no longer able to regenerate on its own. The body responds to such severe events with hyperthermia, massive release of mediators of inflammation and irritation, and with an enormous loss of fluid, which in the past has always and inevitably resulted in the death of people with severe burns. Burns and chills which have led to losses of cutaneous tissue can be compensated by skin transplants and thus the skin can be closed. However, this is successful only if sufficient remaining skin is available for transplantation. In cases of burns of more than 60% of the total cutaneous tissue, transplantation on its own is usually of no assistance. It is necessary to re-produce viable tissue from the remaining skin cells. In this connection, because of the rejection reactions between non-HLA-compatible tissues, it is not possible to take allogeneic skin or allogeneic skin cells. It is therefore necessary to form a new cutaneous tissue in situ from the remaining viable skin cells.
The hornified epidermis forms the protective shield of the skin. For this function to be optimally exercised it is necessary for the skin cells (keratinocytes) to pass through the process of so-called epidermal differentiation. After division of the cells in the basal layer, the keratinocytes migrate to the skin surface and undergo a number of changes during this, until they form the horny layer (stratum corneum) as dead, flat, anuclear corneocytes, and eventually are desquamated. During the epidermal differentiation there is formation of various proteins having specific functions. These include, inter alia, keratins, involucrin, filaggrin and transglutaminase. For optimal formation of the epidermis and the horny layer it is necessary for these proteins to be formed in coordinated fashion and in sufficient quantity.
Many cosmetics, skin care products or wound healing products which help to compensate or at least reduce the disorders of the skin are known in the prior art.
Thus, for example, geroderma is cosmetically treated primarily with vitamin A derivatives or hydroxy acids which lead, via stimulation of the proliferation of the basal cells in the epidermis, to a thickening of the epidermis and thus smoothing of the skin. More recent approaches consist of targeted replacement of the proteins which are absent or present in reduced quantity in dry skin or geroderma, or indirect intervention in the metabolic processes which are disturbed in dry skin or with increasing age, in order to normalize them. An example which may be mentioned here is stimulation of collagen synthesis with the aim of reducing wrinkles. In addition, for example, laminin, substances for prolonging the lifetime of skin cells and certain extracts for stimulating epidermal differentiation are employed. However, some of these are pharmacologically active substances with a high potential for side effects.
None of the preparations known from the prior art on their own enable the skin to reconstitute/regenerate itself without displaying unwanted side effects.
It would be advantageous to have available a preparation which enables the skin to regenerate itself without displaying unwanted side effects.
EP 296078, EP 462426 and U.S. Pat. Nos. 5,116,824, 6,541,023 and 5,808,050, the entire disclosures whereof are incorporated by reference herein, disclose preparations which comprise chitosans, collagens and glycosylaminoglycans. However, none of these documents discloses preparations which support the regeneration of the skin, lastingly improve the skin structure and help the skin to regain its elasticity and healthy appearance.